The present invention relates to safety belt retractors and more particularly to inertially operated safety belt retractors adapted for mounting inside a vehicle door.
In the copending application of William M. Hollowell and Avraham Ziv entitled "VEHICLE SENSING INERTIA REEL LOCKUP INHIBITOR," Ser. No. 872,306, filed Jan. 25, 1978, and assigned to the common assignee of this application, an in-depth discussion is made of various vehicular safety belt systems and one technique for inhibiting, but not preventing, lock-up during the opening of the vehicle door of an inertially operated safety belt retractor of the type mounted within the door of the vehicle to provide upper torso restraint. According to the teaching of said application, an external biasing force is applied to the high inertia mass contained within the retractor activation mechanism during the door opening operation in order to make the high inertia mass more resistive to moving from the unlocked to the locked position during door opening operations. Several embodiments for accomplishing this are shown therein. A separate sensor (mechanical or electrical) is employed according to the teaching of said application to apply and remove the biasing force to the high inertia mass.
While the apparatus of said copending application works well for its intended purposes in many applications, there are some instances where space, monitary, and time/space lag considerations attendant the design of the retractor itself and/or the vehicle in which it is mounted dictate that a simpler, less costly, and/or faster operating inhibition mechanism be employed.
Wherefore, it is the object of the present invention to provide an inhibitor for inertially operated safety belt retractors which is automatically and virtually instantaneously applied during door opening operation of the vehicle.